Worth an estimated $3 million, the Allnatt Diamond is a fancy intense yellow example of the gemstone and is 101.29 carats in size.
It’s named after the British businessman Major Alfred Ernest Allnatt, who owned it during the 1950s. Mystery surrounds its origins before he purchased the stone, but it is believed to have been found in South Africa at the site of what is now the De Beers Premier mine.
Allnatt commissioned Cartier to make a flower setting for it. It was sold for $3 million-plus at Christie’s in Geneva in 1996 to the SIBA Corporation.